Technical Field
The present disclosure relates to a display device, including a display device which can reduce image quality deterioration and touch noise problems, which may occur when a touch sensitive element is applied to a display panel in which a touch sensor is integrated.
Description of the Related Art
Touch sensors that detect a touch input of a user, such as a screen touch for a display device or a gesture, are widely used in display devices public facilities and large-sized display devices, including smart TVs, and the like, in addition to portable display devices including smart phones, tablet PCs, and the like.
The touch sensors may be classified according to a position where the touch sensor is disposed in the display device. The touch sensors may be classified as: an in-cell type touch sensor, in which the touch sensor is embedded in a display panel; an on-cell type touch sensor, in which the touch sensor is positioned on the top of the display panel; an add-on type touch sensor, in which a separately manufactured touch sensor is separately disposed on the top of the display panel; and a hybrid type touch sensor, in which different types of touch sensors are combined. Among the various types of the touch sensors, the add-on type sensor has a disadvantage in that the thickness of the display device, and the corresponding manufacturing cost, increases because a separate touch sensor needs to be attached to the top of the display device. It is also difficult to attach the add-on type touch sensor to a flexible display device. Therefore, in recent years, there has been an increase interest in integrating the touch sensor in the display device by using the in-cell type touch sensor to provide a light and thin display device.
Meanwhile, research into a haptic device that does not just detect the touch input of the user but also transfers a tactile feedback, which may be felt with a finger of the user or a stylus pen of the user, as a feedback for the touch input of the user has been pursued in recent years.
As the haptic device, a haptic device adopting an eccentric rotating mass (ERM), a linear resonant actuator (LRA), a piezo ceramic actuator, and the like, have been used. However, such haptic devices are problematic in that the haptic devices: are made of an opaque material, vibrate the entirety of the display device rather than a specific part of the device; cannot provide various vibration feels; and may be easily broken by external impact due to low durability.
Further, when the driving voltage of the haptic device, which is required for transferring the tactile feedback to the user, a touch may not be recognized or an image may not be displayed normally due to noise generated due to the high driving voltage, which is also problematic.
Accordingly, there is a need for applying a haptic device acquired by solving the problems to the display device in which the touch sensor is integrated.